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How to determine whether a Pandas Column contains a particular value
...s)
Out[24]: True
As pointed out by @DSM, it may be more efficient (especially if you're just doing this for one value) to just use in directly on the values:
In [31]: s.values
Out[31]: array(['a', 'b', 'c'], dtype=object)
In [32]: 'a' in s.values
Out[32]: True
...
How to get Ruby / Homebrew / RVM to work on Yosemite?
After installing Yosemite, I was unable to run brew or ruby.
11 Answers
11
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How do you squash commits into one patch with git format-patch?
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This is what I use when I want to keep the history locally (in case I need to edit the patch). Otherwise I just use rebase -i and squash the commits.
– sebnow
Mar 9 '09 at 5:23
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Generate all permutations of a list without adjacent equal elements
...is greedy algorithm returns optimal solutions, by the following logic. We call a prefix (partial solution) safe if it extends to an optimal solution. Clearly the empty prefix is safe, and if a safe prefix is a whole solution then that solution is optimal. It suffices to show inductively that each gr...
Git for beginners: The definitive practical guide
...repository.
cd ~/code/project001/
rm -rf .git/
Caution: This will destroy all revision history, all your tags, everything git has done. It will not touch the "current" files (the files you can currently see), but previous changes, deleted files and so on will be unrecoverable!
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How to send a header using a HTTP request through a curl call?
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In PHP:
curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue'));
or you can set multiple:
curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue', 'HeaderName2:HeaderValue2'));
...
Non-static variable cannot be referenced from a static context
... what you see with the class "car". The class contains which is similar to all cars. Think of it as a template or an idea.
At the same time, the car you see is an instance of the class "car" since it has all the properties which you expect: There is someone driving it, it has an engine, wheels.
So...
What is The Rule of Three?
...in various contexts,
and we should understand what "copying an object" actually means.
Let us consider a simple example:
class person
{
std::string name;
int age;
public:
person(const std::string& name, int age) : name(name), age(age)
{
}
};
int main()
{
person a("Bjar...
Which equals operator (== vs ===) should be used in JavaScript comparisons?
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The strict equality operator (===) behaves identically to the abstract equality operator (==) except no type conversion is done, and the types must be the same to be considered equal.
Reference: Javascript Tutorial: Comparison Operators
The == operator will compare for equ...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
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@mrsoltys, quantum computers are "only" exponentially faster for some problems, they can not solve undecidable problems.
– zch
Jul 1 '13 at 18:52
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